Fatty acid identification by GC-MS

The extracted fatty acids were prepared with fatty acid methyl esters (Berton et al., 2016 (link)). The fatty acids were separated by an Agilent 5977B GC/MSD (Agilent, CA, United States) using a 100 m × 0.25 mm diameter SP-2560 capillary column of 0.02 mm thickness (Supelco, Bellefonte, PA) (Ebrahimi et al., 2014 (link)). Helium was used as a carrier gas with a spit ratio of 9:1. The experimental conditions for mass spectrometry were as follows: full scan mode, a solvent delay of 11 min, a gain factor of 10, an ion source temperature of 230°C, and a quadrupole temperature of 150°C. Qualitative Analysis B.07.00 software (Agilent) was used with the National Institute of Standards and Technology (NIST) database to identify the compound information for the reference standard (Sigma-Aldrich, United States) and samples. The results are expressed as a percentage of total fatty acids.